Here is a note from Gibb over on the "Advent & Development of Chanties" thread with a reference to the singing of "Sally Brown" by sailors in the gold mines of California in 1852. This is an important find! It is one of the very few instances where we have any mention of any chanties being sung in relation to the Gold Rush, from that actual period.

Subject: RE: The Advent and Development of Chanties
From: Gibb Sahib - PM
Date: 10 Jan 11 - 01:48 AM

1855 Marryat, "Frank". _Mountains and Molehills_. London: Longman, Brown, Green. and Longmans.

Marryat is mining at Tuttletown (Tuolumne County) in California during the Gold Rush. It is January 1852.

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A sailor in the mines is at best a rough and uncomely fellow to the sight; but will you show me anything more pleasing to contemplate than that sturdy fellow there who plies his pickaxe to the tune of " Oh, Sally Brown! " that he may take at night to his sick friend in the tent hard by the luxuries he needs ? The sailors in the mines have been ever distinguished for self-denial; and whenever I see " prim goodness" frown at the rough, careless sailor's oath that will mingle now and then with his " ye-ho ! " I think to myself, " Take out your heart, 'prim goodness,' and lay it by the side of Jack's and offer me the choice of the two, and maybe it won't be yours I'll take, for all that you are faultless to the world's eye."
//

The son of Frederick Marryat would certainly know "Sally Brown."